Raster Graphics Editor is a computer program that allows users to paint and edit pictures interactively on the computer screen and save them in one of many popular “bitmap” or “raster” formats such as JPEG, PNG, GIF and TIFF.
Krita is a raster graphics editor powered by KDE program designed for sketching and painting. It is free and open-source software under the terms of GNU General Public License (GPL).
Krita intended to be suitable for all your image creation and editing needs, such as creating original art, making images for websites, touching up scanned photographs or anything else you might need to do with bitmapped images.
Krita is available for all version of of Windows, Mac OS, Linux and many more.